Briquet.



UNITED STATES I'Patented May 19, 1903.

PATENT OFFICE.

ARTHUR w. CHASE, onaggdvooA, IOWA.

BRIQUET.

SPECIFICATION forming part of Letters Patent No. 728,369, dated May 19,1903. Application filed February 28, 1899. Renewed October 1, 1902.Serial No. 125,601. (No model.)

To all whom it may concern:

Be it known that I, ARTHUR W. CHASE, a citizen of the United States,residing at Avoca, in the county of PottaWatt-amie and State of Iowa,have invented certain new and useful Improvements in Briquets; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit appertains to make and use the same.

My invention relates to an improvement in briquets made from ores of thebrown hematite class mixed with powdered blue-billy.

The operation of making the briquets is as follows: Ores of the brownhematite class (2Fe O3.3H O)that is to say,hydrated ferric oxidarefinely pulverized and mixed in any suitable dry mixer with thepulverized purple ore or blue-billy obtained as a by-product in themaking of sulfuric acid. The proportions of the hematite ores and theblue-billy may vary very widely; but in practical treatment of certainores which I have actually used I find that from ten to twenty per cent.of the brown hematite ore, (2Fe O3.3H O,) especially if it carriesconsiderable alumina, makes excellent briquets when mixed with fromeighty to ninety per cent. of blue-billy. As soon as the hematite oreand blue-billy have become thoroughly incorporated with each other asmall proportion of steam,or preferably steam mixed with carbonic acid,(00 is admitted to the mixer,enough steam being used to slightly moistenthe mixture. This moist mixture is then pressed into briquetsandforconvenience is usually subjected to a preliminary drying,

although this is not necessary. These briquets are then baked at a redheat. At this temperature the water of crystallization contained in thebrown hematite ores is driven off, leaving the. red oxid, (FY9 0 for theblue-billy. Moreover, certain chemical changes occur, as an analysis ofthe briquets shows the presence of a certain quantity of the magneticoxid of iron, (Fe O Many of the brown hematite ores carry a considerablepercentage of aluminium in combination, running as high in someinstances as fifteen or twenty per cent. This acts as an additionalbinding agent and is in no way harmful in the succeeding processofsmelting. The briquet obtained has certain marked and distinctiveproperties. It is a homogeneous mass, all the parts thereof beingfirmly'combined together. It is slightly porous, as in the operation ofbaking the water admixed being driven ofi leaves spaces behind. Thisphysical property renders them better suited for blast-furnace work andeasier to reduce, for the reason that the reducing agents can get intothe interior structure of the briquet more easily than would be the caseif the briquets were perfectly solid, it of course being understood thatthese briquets are prepared especially to be smelted in a blast-furnace.The chief ad vantage of these briquets, however, is that they will standthe heat and pressure to which they are subjected in a blast-furnaceduring the operation of smelting without disintegration, and so far as Iam aware no briquets have ever been produced prior to my presentinvention which possess these qualities.

Ordinary briquets when put into blast-furnaces disintegrate very readilyunder the heat and pressure to which they are subjected. They therebyclog the furnace, and much of this substance is carried off in theblast, clogging the stoves, and entailing waste, and this fact rendersthem useless in blast-furnace work, except in very small quantities whenused in connection with other ores. Briquets formed in the manner abovedescribed are entirely free from this objection.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent of the United States, is-

A briquet composed of pulverulent brown hematite ores and powderedblue-billy fritted or fused together, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

ARTHUR w. cnAsE.

Witnesses: I

JOHN CHALMERS WILsON, J OHN I-I. HOLT.

